Twinkle: Faceting Design Diagram
Successful tips, details and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Twinkle"
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Twinkle (MIR40.JRG)
By Jeff R. Graham
Copyright 2004
86% Light Return
Angles for R.I. = 1.62
40 facets + 6 facets on girdle = 46
3-fold, mirror-image symmetry
96 index
L/W = 1.155 T/W = 0.385 T/L = 0.334
P/W = 0.397 C/W = 0.212
H/W = (P+C)/W+0.02 = 0.630
P/H = 0.631 C/H = 0.337
Vol./W^3 = 0.239
Addition # 9 - This is not hard to cut, but the meets can be a little tough from a technical standpoint. This works well in any material. Cut in refractive indexes 1.62 to 1.76 with no changes. This is nice in Garnet.
Random - Cosine - ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
Jeff R. Graham
The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.
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